PERFORMANCE: Barts Health Trust has apologised to patients in east London after their blood test results were contaminated by an equipment fault at its Whipps Cross Hospital site.

GPs were forced to tell patients to be re-tested after their results came back showing elevated levels of ‘mean cell volume’, a measurement of red blood cell size which some patients thought was a marker of cancer.

A trust investigation revealed that the results of a “small number of patients” had shown elevated MCVs because of a problem with the performance of an analysis machine.

 A spokesman for Barts said: “The patients concerned were all retested and found to have normal results.

“While no patient suffered any actual harm, we would like to apologise for any anxiety they experienced waiting for their test results.”

“We immediately investigated the matter and found this year’s high summer temperatures led to performance issues with the haematology analysers.

“Regrettably, this resulted in a small number of patients’ blood tests showing raised levels of MCV”.

All blood samples from GP practices are now tested at the Royal London Hospital “to avoid any such errors happening again”, he added.

Waltham Forest Clinical Commissioning Group’s October board papers says the trust had “admitted there was a problem with the air conditioning” but that this information was “not passed onto the GPs”.